Desktop computer conferencing system

ABSTRACT

A man-computer-man communications system, including a computer workstation ( 10 ), which is comprised of a display device ( 22 ), graphic tablet ( 18 ), stylus ( 14 ), computer unit ( 24 ), and display device screen ( 16 ) located at convenient locations. The active area of the graphic tablet is a transparent surface area ( 18 ), which is coincident to the display screen and is approximately the same size as the display screen The graphic tablet device may include active or passive stylus ( 14 ). A keyboard unit ( 12 ) and telephone unit ( 28 ) may be added to the workstation. An external communications system may be added to transmit and receive data to or from remote computers or other workstations. The computer unit ( 24 ) controls the operation of the workstation and external communications.

RELATED APPLICATIONS

This present application is a continuation application of Ser. No.08/487,778 filed Jun. 7, 1995; which was divisional application of Ser.No. 08/280,148 filed Jul. 25, 1994, which was a continuation applicationof Ser. No. 07/771,856 filed Oct. 7, 1991, which was a Continuation inpart application of Ser. No. 07/375,366 filed on Jul. 3, 1989. Each ofthe related applications is incorporated herein by reference in itsentirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to communication systems used by individuals forgeneral tele-writing, sketching and drawing of hand written information,to be transmitted to other individuals via computer systems. Inparticular it relates to computer workstations comprised of electricaland mechanical devices for the input, computation, and output of data,resulting an integrated ergonomically designed human-computer interfacesystem.

2. Description of the Prior Art

In the following, a computer workstation is defined to be a combinationof devices and apparatus, which may include computer hardware andsoftware, that a person uses or operates during the performance variouscomputing and communication tasks. These tasks includes, but is notlimited to, technical calculations, business computations andlocal/remote communications. Prior art in this field includes manycomputer workstations and personal computers. Henceforth, a computerworkstation will include personal computers, computer terminals,computer consoles, and like devices. The person operating theworkstation will be referred to as the user. Display devices used incomputer workstations can be classified into two broad categories. Thefirst category is often referred to as direct-view display devices, inwhich the user, looks directly at the actual display screen, notprojected light image from other components. Most of the display devicesin the prior art belong to this category, examples include the CathodeRay Tube (CRT), liquid crystal, and plasma panel displays. The othercategory is referred to as non-direct view or projected image displays,where examples include the optical CRT projector and some laseraddressed liquid crystal projection devices.

There are presently many computer workstations on the market, manyhaving similar components and physical arrangements. The availableworkstations are very well known to those skilled in the workstationart. The majority of computer workstations have a CRT display deviceplaced on the table or desk, a mouse unit, a computer unit, and analphanumeric keyboard. The prior art CRT or other direct-view displaysusually have the display screen at near vertical or near 45 degreescreen inclinations. A graphic tablet is defined to be an electricaldevice, which repeatedly measures the position of a stylus, pen or auser's finger over a defined area, encodes the positions into a digitalsignal, and transmits the data to a computer. A stylus is defined to beany elongated pen-like object that can be used for writing or sketching,including the user's finger. The writing stylus is typically used topoint, write, sketch, or draw onto the graphic tablet's active area,referred to as the encoding area.

Prior art in computer workstations exist in various combinations ofcomputers, display devices, and peripheral devices. However, the priorart fails to anticipate the importance of computer workstation withcomputer, graphic tablet, and display device, with inclined screen angleand its adjustability through large angles. U.S. Pat. No. 4,361,721 ofDagnelie discloses a teletext device having a graphic tablet and a CRTdisplay at a screen inclination fixed near 45 degrees. However, thedisclosure does not recognize display screen angle adjustability anddoes not teach a computing means of any type, which severely limits theusefulness of the device. U.S. Pat. No. 4,562,482 of Brown discloses acomputerized executive workstation having a CRT display with a screeninclination angle of 50 degrees from the horizontal, during workstationoperation. Although the CRT display can be retracted to a storedposition below the work surface area, the teachings of Brown do notdisclose a graphic tablet and do not disclose screen angleadjustability. These shortcomings restrict the workstation an operationwithout graphic input. The U.S. Pat. No. 4,668,026 of Lapeyre andGundlach discloses a computer terminal cabinet for glare reduction,having a CRT display at an acute angle with the horizontal, a keyboard,and a printer. The reference teaches adjustable mounting only for glarereduction, and does not disclose a graphic tablet or a computer; thusalso restricting the terminal to non-graphic input. U.S. Pat. No.4,669,789 of Pemberton discloses a computer user's desk having a CRTmonitor at about 60 degrees from the horizontal, a keyboard, and dualdisk drives. This reference does not disclose a graphic tablet or screenangle adjustability to inclinations near the horizontal. Again, theprior art does not anticipate graphic input or screen angleadjustability for optimal stylus control.

All the prior art of computer workstations, terminals or cabinets, ofwhich the above is representative, disclose either display screens nearvertical orientation, disclose fixed acute inclinations, or limitedscreen angle adjustability for glare reduction. No prior art can befound that disclose screen angle adjustability from horizontal tovertical, with a graphic tablet and computer. The prior art workstationscan be used in either the conventional manner or at a fixed acute screenangle, but not both. The prior art fails to recognize the importance ofan ergonomically design graphic input workstation capable of adjustingbetween conventional orientation and graphic input mode of operationwith stylus data entry and screen angle near the horizontal (about 30degrees for horizontal).

Although several graphic tablet and stylus devices are available in themarket, they usually have been combined with a display device byelectrical means only. The typical display and graphic tabletcombination has an opaque tablet laying horizontally on the desk ortable next to the display device, connected by an electrical cable. Somegraphic tablet prior art includes a transparent tablet placed over thedisplay screen, but typically the screen orientation is near vertical.Although this arrangement works satisfactory for general purposecomputer processing, it has some definite shortcomings when highresolution graphic processing is attempted. This is important becausetoday software is becoming more graphic intensive than ever before.

An important problem exists if the screen angle is near vertical. Theuser's hand and wrist must bend to an uncomfortable position to write orsketch on the tablet-display surface. In addition, if the screen is ateye level, as with most prior art, the user's arm must be raised andheld at position that will become very tiresome to the user, if used fora significant amount of time. The above is not just a matter ofconvenience. These shortcomings have severely restricted the use ofstandard graphic tablet input devices in the marketplace. This is onereason that the mouse input device has found wide spread use as agraphic input device for computer workstations and personal computers.Specifically, the mouse unit slides over the work table or desk,providing a support for the user's hand and arm. However, the mousegraphic input devices also have several disadvantages. First, it isdifficult for the user to write, sketch, or draw with a mouse, becausethe device is too large and bulky to act as a pen or stylus. Secondly,the device must have a clear area on the table or desk for the unit toslide. This is valuable work space that some workstations cannot affordto lose.

Prior art workstations are inherently limited in their graphicinteraction capabilities. The use of mice, joysticks, trackballs, andtouch panels all have limitations for entering positional and functionaldata. For example, Computer-Aid Design (CAD) and Computer-Aided Designand Drafting (CADD) applications require precise and natural drawing andpointing means. An engineer or draftsman must be able to work at theirworkstation all day without great mental or physical fatigue. The priorart also does a poor job at providing a fatigue free workstation. In thearea of teleconferencing applications, the computer workstation must becapable of real-time graphic and voice communications. The prior artworkstations do not provide the means to accomplish that type ofcommunications. In addition, conventional prior art workstations do notprovide the ergonomically designed hardware support necessary forreal-time electronic mail communications, while connected to either inLocal Area Network communication means or remote communication means.

SUMMARY OF THE INVENTION

The disclosed invention solves the shortcomings of the prior art byarranging the standard workstation components so that it results in anintegrated ergonomically designed universal workstation. The primaryfeature of the workstation is that its display device is oriented sothat its screen angle is inclined at an angle. A transparent graphictablet or stylus encoding means is placed over the display screen suchthat tablet or encoding area is parallel to the screen and above with aminimum space between them. Thus the tablet and screen appear to be onesurface to the user. The display and tablet combination can be made tobe adjustable through a multiplicity of screen angles. When the userwrites with the stylus onto the tablet-surface and the surface isoriented at an angle of about 30 degrees, a natural writing and displaysurface exits, which provides a surprisingly synergistic and naturalman-computer interface. In addition, the same workstation can be usedfor standard personal computing.

Accordingly, the present invention has for its first object a computerworkstation with a display device oriented at an inclined angle near thehorizontal such that the user can write, sketch or draw on the displayscreen-tablet surface it a natural manner, where it results in a new andsurprising tele-writing, tele-drawing, and voice-graphics conferencingsystem.

Another important object of this invention is to provide anergonomically designed computer workstation integrating text, graphics,and voice means for the purpose of general purpose computing andcommunications.

A still another important object of this invention is to provide for ahuman-computer interface that results in a natural, easy to use, anduseful computer workstation, personal computer, computer terminal,personal workstation, and/or computer console.

A further object of this invention is to allow precise hand controlledstylus pointing, sketching, writing, or drawing functions by a user fordata entry into a computer means, computer network, distributed network,or communication system.

A still further object of this invention is to provide a workstationwith graphic input and output means integrated with two way telephonevoice means, such that real-time teleconferencing is made possible fromthe same workstation herein.

Another important object of this invention is to provide a computerbased workstation capable of real-time electronic mail functions. Thiswould involve communicating alphanumeric text, graphics, and images toremote locations, and having a capability of transmitting the user'shand writing, including his or hers personal signature, via electronicmail messages.

A further object of this invention is to provide an improved computerworkstation for Computer-Aided Design and Computer-Aided Design andDrafting applications, as well as general purpose high resolutiongraphic image rendering systems.

Still further objects and advantages will become apparent from aconsideration of the ensuing description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the computer workstation in accordancewith the present invention.

FIG. 2 is a right side view of a CRT monitor embodiment of theinvention, showing a hidden view, an exploded view and a break awayview.

FIG. 3 is a right side view of the flat panel display embodiment of theinvention, showing hidden view, an exploded view and a break away view.

FIGS. 4A and 4B are a flow chart of one application of the inventionshowing the sequence of the stored program events during the operationof the computer workstation.

DETAILED DESCRIPTION

The disclosed invention can be described with reference to theperspective view of FIG. 1, which shows one possible embodiment. Thecomponents of the computer workstation may be arranged in severaldifferent embodiments. In FIG. 1, a table support 26 physically supportsa display device 22, a transparent graphic tablet surface area 18, astylus 14, a computer keyboard unit 12, a mouse unit 15 and a computingmeans 24. The table support 26 may be a standard desk or pedestal,modified to physically support the above components, or it may be aspecially design structure. All display devices define a display screenof a finite area. The display device 22 has a display screen 16, whichis located under the graphic tablet surface 18 and is of equivalentsize, as indicated in the figure. The display screen is inclined at anangle between the horizontal and 45 degrees. The angle of inclination isadjustable through a wide range of angles. The display device 22 hascontrol circuitry which may internal to the screen housing or locatedsome distance away. The control circuity may have one or moremicroprocessors associated with it.

The graphic tablet surface 18 may consist of a thin layer of atransparent material such as indium tin oxide or other suitablematerial; thus it cannot be distinguished for the display screen 16 inFIG. 1, but can be seen in FIGS. 2 and 3 in exploded view. The stylus 14has an electrical cable 20 connecting it to the computing means 24. Thegraphic tablet surface 18, the stylus 14 the stylus-computer cable 20and its control electronics make up a stylus position encoding means.The control electronics is typically located on a printed circuit cardinside the computing means. Stylus encoding means are well known tothose skilled in the art. The mouse unit is comprised of a hand unit andelectrical cable, which is connected to the computing mean's serial portor bus interface.

A telephone means 28 may be located on table support means near thedisplay device and keyboard. The addition of the telephone means to thecomputer workstation provides for both voice and data communications,simultaneously. The telephone means may be connected to the computingmeans 24 via an electrical telephone-computer cable 29. Specificcircuitry in the computing means may integrate the voice signals withtext/graphic data, well known to those skilled in the art. The computingmeans may be connected to an external communication means fortransmitting and receiving data to and from a communications network 52.The electrical connection to the communications network is via anexternal communications cable 49. The communications network 52 isdefined to be any appropriate communication system or network, in whichdata is transmitted and/or received to and from local or remote devices.Examples of such a communication network include the conventionaltelephone system, private telephone exchanges, computer local areanetworks, wide area networks, RS-232 serial interface, and many othertypes of communication systems. The telephone means 28 may be aspeaker-type telephone, where the hands of the user are free to type onthe keyboard or to write with the hand-held stylus. In an alternativeembodiment, the telephone means may be connected directly to thecommunications network without going though the computer means. In analternative embodiment, the computing means' functions may beincorporated into the display control circuitry.

The computer keyboard unit 12 may be a standard alphanumeric typekeyboard or a special application specific keyboard design. As shown inFIG. 1, the keyboard unit is mounted in front of the workstation foreasy access by the user. The keyboard is electrically connected to thecomputer with a cable in the standard manner, well know to those skilledin the art. The computing means 24 may be located in several differentpositions, but a convenient position may be vertical mounted under thetable support 26, as shown in the figure.

FIG. 2 shows a right side view of one embodiment of the computerworkstation, embodied with a CRT display monitor 40, which is a specifictype of display device. For clarity, this figure does not show thetelephone means 28, but it does show the telephone-computer cable 29.Some elements of the figure are shown with hidden lines and otherelements are shown in a break-a-way view.

The computer workstation 10 may be realized with several types ofcomputers or processors, having a wide range of processing powers,capabilities and sizes. Typically, the computing means 24 will have acentral processing unit, internal memory, arithmetic logic unit,internal data bus, memory bus, device controllers, and other componentwell known to those skilled in the art. The computing means 24 will alsoprocess stored programs, algorithms and software, including but notlimited to machine language, operating system, assembly languages, highlevel computational languages, and application software. The softwaremay include text and graphic primitive programs to assist in thegeneration and manipulation of text and graphic workstation functions.Such software is known to those skilled in the field.

The means to encode a stylus position over the tablet area intoelectrical signals can be accomplished by several techniques. Among theprior art of encoding means are (1) measurement of x and y time delaysvia surface acoustic wave, (2) surface resistive sheet, (3) membranepressure, (4) magnetic field means and (5) air acoustic means. In someembodiments, the tablet surface maybe a thin film applied to the displayscreen. In other embodiments, the tablet or encoding area may representan area on the display screen, without a physical embodiment; i.e., airspace between sensors. There are many types of graphic tablets that arepresently on the market, including the SummaSketch® from SummagraphicsCorporation, E-Z Inage™ from Ovonic Systems Inc., or Scriptel™ fromScriptel Corporation. Typically, the stylus position is measured at arate of about 100-500 points/second in both the x and y directions overthe tablet's active area. The tablet electronics, located near thetablet, in the stylus, or on the tablet-computer interface card,converts these measurements into a digital code (encoded) and arrangedinto digital words or bytes (typically, 8 or 16 bits long). Theresolutions of these devices are in the 200-300 dots/inch range.

As presented in FIG. 2, the graphic tablet means is comprised of thegraphic tablet surface 18 and the stylus 14 elements. They are presentedin an exploded view, in order to show the reader the distinction betweenthe tablet and the display screen 16. The space shown between elements16 and 18 would not be apparent in the disclosed embodiment. The stylus14 is shown with the cable 20 connecting it the computing means. Theterm graphic tablet and stylus encoding means are equivalent. Dependingon the type of graphic tablet employed, the cable may not be necessary.The cable can be removed if the stylus contains small batteries forelectrical power. Electrical cable 20 connects the graphic tablet to thecomputing means 24 for control. The electrical interface between thetablet and computing means can be a serial RS-232 interface, a parallelbus interface, or other standard computer-device interfaces. In FIG. 2,at least one electrical cable 42 connects the CRT monitor 40 to thecomputing means 24 for control of the display functions. The electricalinterface is of the standard type well known to those skilled in thedisplay terminal or workstation field. Typically, either digital TTLsignals (representing video) or analog RGB video signals are provided tothe CRT monitor.

Many types of CRT display monitors could be used in the workstation, butit is preferred that a relatively high resolution (70 dots/inch orhigher) flat screen type be used. One possible candidate CRT that ispresently available is the Zenith™ Data System's Model ZCM-1490 FlatScreen CRT Monitor. This monitor is a color CRT display capable ofdisplaying the IBM® V GA Standard 620×480 pixels at a center screenpitch of 0.28 millimeters. This resolution is sufficient for reasonablequality graphics. The main advantage of the monitor is its flat screen.For the invention disclosed here, the flat screen results in a naturalwriting surface, when combined with a graphic tablet. Other curvedsurface CRTs could be used, but a flat screen is a preferred embodiment.Although either monochrome or color display could be used, colordisplays are preferred, because they can produce a high brightnessbackground color, for example white. A bright display background isimportant in order to reduce the perceived glare from the display-tabletscreen. Of course, color displays are also preferred because of improvedhuman information recognition, well known in the human factors field.

Instead of a CRT display monitor, the workstation may be embodied with aflat panel display device. One possible embodiment is shown in shown inFIG. 3 with flat panel display device 27. Flat panel displays devicesinclude electroluminescent, liquid crystal, plasma, electrochromic, andelectrophoretic display technologies. The primary characteristic ofthese type displays is the relatively thin structure with a lack ofbulkiness. This lack of depth is an advantage since it reduces the massand volume of the display device. This makes it easier to manufacturethe computer workstation, resulting in a lower cost and an improvedergonomically designed workstation.

Since a relatively high resolution display device is required in thissystem, the active matrix liquid crystal display (LCD) panel is apreferred flat panel technology of choice. The advantages of LCD panelsare their low power, light weight, VGA resolution, and the possibilityof color. Presently, the disadvantages of LCDs are their high cost, lowbrightness, low contrast, and limited grey scale and color. The otherdisplay technologies have even greater limitations, making it difficultto realize a useful display device. This however, may change in thefuture when improvements in flat panel display technology willundoubtedly be made. The electrical signals between a flat panel displayand the computing means, carried by cable 42 of FIG. 3, differ from thatof the CRT. Flat panel displays are typically driven by matrixaddressing techniques, requiring significant circuitry to be located ator near the panel. Data to be transferred between the display and thecomputing means will consist of digital words containing a number ofbits for x and y addresses, write and erase data, color information,scan data, etc. Such interfaces are well known to those skilled in theart of display technology.

The other elements of FIG. 3, with like element numbers, are equivalentto those of FIG. 2. The preferred workstation embodiment is the oneusing flat panel display device 27 and display orientation adjustmentmeans 50 as shown in FIG. 3. One reason for this preference is the easeof adjusting means and potentially better quality display. However, thelow cost of CRT monitors may be an advantage if the cost continues to beless than equivalent flat panel displays.

FIGS. 4A and 4B presents a flow chart of one possible implementation ofthe software that would be executed in the computing means, includingcentral processor unit or control circuitry. If a computer is embodiedin the invention, the software would reside in stored programs residingin memory of the computer. The memory may be semiconductor, magnetic,optical or other memory types. The sequence starts with the power-onswitch selection, which starts the power-up initialization program 60.The term program, as used here, is equivalent to an algorithm orroutine, implemented in computer software. The next program step is thesystems diagnostics and checkout program 62 that has either of twooutputs: PASS or FAIL. If any of the tested components FAIL the test,data is sent to the system error report 64 program. If the systemspasses, the operator is asked to select the mode of operation 66, viathe keyboard, mouse or graphic tablet. If a terminal emulation mode isselected, the mode is initialized 70. The terminal mode is defined to bean operational mode where the workstation acts as a conventionalcomputer terminal or communications terminal. If it is to act as acommunications terminal, voice data from the telephone means may becommunicated as well as text and graphic data. The user is asked whetherthe voice communications 72 option is desired; if so, a program tocontrol the voice communication is initiated. In either case, a terminalcommunication program and modem program 80 is initialized. Next, theterminal mode program is set up 92 and the terminal application programis loaded 94. Exit from the terminal mode is allowed, along withoperation stop and power off.

If the workstation mode is selected in element 66 of FIG. 4A, theoperating system is booted 68. The user is then asked to select either astand-alone or a network mode 74. If a stand alone mode is chosen, thatmode is initialized 82, a windowing environment program may be loaded90, and setup for an application program is accomplished 96. If thenetwork mode is selected, the network communication's programs areinitialized 76, and the user is asked whether the voice communicationoption is selected 84. If so, the voice communication program isinitialized, which notifies the program that simultaneous voicecommunications via the telephone means will take place, with both textand graphic data communications. The voice signals may be integratedwith the digital text and graphics data, or it may be transmitted andreceived via a separate cable to the communications network. A LocalArea Network (LAN) or a remote communications programs are then loaded88. If necessary, certain data or programs may be downloaded 98 to theworkstation from a remote host or workstation. Elements 88 and 98 bothinput into the load window environment program 90.

Following element 96 of FIG. 4B, the user is given the opportunity ofselecting and initializing the memory and I/O devices 100, which areavailable to the workstation. The required application program orprograms are then loaded into the workstation memory. A wide variety ofapplication programs could be loaded, including, but not limited to, arealtime tele-writing conferencing program 106, CAD/CADD applicationprograms 108, word processing and/or desktop publishing programs 110,business/finance application programs 102, and scientific andengineering application programs 104. The user can exit from theapplication program or go to another application setup 112. The user canalso either exit the operating mode 114 or go to the mode of operationselection element 66. If the exit from the operating mode is selected,the system stop and power-off switch can be selected.

The scope of the invention disclosed here should be determined by theappended claims and their legal equivalents, rather than by the examplesgiven above.

1. A display-tablet device comprising: a) a microprocessor computersystem running a personal computer-type operating system program; b) aflat panel display device defining a display screen controlled by themicroprocessor computer system; c) a transmissive graphic tablet inputdevice placed over the flat panel display screen, wherein the graphictablet input device is controlled by the microprocessor computer system,and wherein a user has an option to enter data to the graphic tabletusing a stylus; d) a control button on the front top surface of theportable display-tablet device for additional user control or data inputto the portable display-tablet device; e) an enclosure in which themicroprocessor system and other necessary support components arelocated.